We present an empirical model for the nearballistic transport in carbonnanotube (CNT) transistors used as strain sensors. This model describes theintrinsic effect of strain on the transport in CNTs by taking into accountphonon scattering and thermally activated charge carriers. As this model relieson a semiempirical description of the electronic bands, different levels ofelectronic structure calculations can be used as input. The results show thatthe electronic structure of strained single-walled CNTs with a radius largerthan 0.7nm can be described by a fully analytical model in the sensing regime.For CNTs with smaller diameter, parameterized data from electronic structurecalculations can be used for the model. Depending on the type of CNTs, theconductance can vary by several orders of magnitude when strain is applied,which is consistent with the current literature. Further, we demonstrate thetuning of the sensor by an external gate which allows shifting the signalamplitude and the strain sensitivity. These parameters have to be balanced toget good sensing properties. Due to its basically analytical nature, thetransport model can be formulated as a compact model for circuit simulations.
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